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Particle image velocimetry (PIV) data are a valuable asset in fluid mechanics. It is capable of visualizing flow structures even in complex physics scenarios, such as the flow at the exit of the rotor of a centrifugal fan. Machine learning is also a successful companion to PIV in order to increase data resolution or impute experimental gaps. While classical algorithms focus solely on replicating data using statistical metrics, the application of physics-informed neural networks (PINN) contributes to both data reconstruction and adherence to governing equations. The present study utilizes a convolutional physics-informed auto-encoder to reproduce planar PIV fields in the gappy regions while also satisfying the mass conservation equation. It proposes a novel approach that compromises experimental data reconstruction for compliance with physical restrictions. Simultaneously, it is aimed to ensure that the reconstruction error does not considerably deviate from the uncertainty band of the test data. A turbulence scale approximation is employed to set the relative weighting of the physical and data-driven terms in the loss function to ensure that both objectives are achieved. All steps are initially evaluated on a set of direct numerical simulation data to demonstrate the general capability of the network. Finally, examination of the PIV data indicates that the proposed PINN auto-encoder can enhance reconstruction accuracy by about 28% and 29% in terms of mass conservation residual and velocity statistics, respectively, at the expense of up to a 5% increase in the number of vectors with reconstruction error higher than the uncertainty band of the PIV test data. [ABSTRACT FROM AUTHOR]

Solar heat transfer fluid (HTF) plays a crucial role in the performance of parabolic trough solar collectors (PTSC) and the energy systems integrated with them. In this study, a multi-attribute decision-making (MADM) analysis is employed to prioritize the HTFs for three solar-driven multi-generation energy systems. These systems are based on a direct-fed organic Rankine cycle (ORC) and bottom-cycle arrangement of a double-effect absorption refrigeration cycle and a Kalina cycle system. The ORC configurations include simple, regenerative, and ORC integrated with an internal heat exchanger. The MADM analysis shows that the optimal HTF for all systems is Therminol 66 for which ORC based system demonstrates the best performance in both energy (80.17 %) and exergy (33.21 %) viewpoints. Additionally, this system exhibits the highest performance in terms of net present value (82.6 M$), dynamic payback period (2.19 years) and cost of energy (0.018 $/kWh). [ABSTRACT FROM AUTHOR]

Objective(s): Obesity is a metabolic syndrome that leads to many chronic diseases worldwide. In this study, we investigate the antihyperlipidemic activities of chitosan nanoparticles (CH NPs) on silymarin (SIL) as a carrier in the drug delivery system that can improve some biochemical parameters and hormones in the model of hyperlipidemic rats receiving a high-fat diet (HFD). Materials and Methods: Physicochemical characterization of silymarin-loaded chitosannanoparticles (CH-SIL NPs) was done by Fourier-transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and drug loading efficiency (LE). Diet-induced hyperlipidemic rats were treated with SIL (15 mg/kg/day) and CH-SIL NPs(15 mg/kg/day) for twelve weeks orally daily. The body weight loss (BW), food consumption, serum total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), levels of fasting blood glucose (FBG) in serum, serum insulin, cortisol, testosterone, and brain neuropeptide Y (NPY), Y1 and Y5 receptor mRNA expression were analyzed. Results: A significant reduction in BW and food consumption from 417 ± 16 g and 33 ± 1.03 in group HFD to 338 ± 10 g and 17.33 ± 1.02 in group CHS+HFD was observed, respectively. This data revealed that CH-SIL NPs improved hyperlipidemia, hyperinsulinemia, and hyperglycemia, reduced serum cortisol, and down-regulated NPY and Y1R with a significant increase in HDL and testosterone hormones compared to the control group. Conclusion: The developed Sil-loaded CH NPs were good agents for improving efficacy. It is the first report of the proposed weight loss mechanism of SIL CH NPs, thereby providing information about the anti-hyperlipidemic and antihyperglycemic effects of silymarin-loaded chitosan nanoparticles, a natural food with proper effects against metabolic disorders in case of hyperlipidemia that may lead to obesity and up-regulation of brain NPY. [ABSTRACT FROM AUTHOR]

It is crucial to evaluate the impact of key parameters of multi-generation systems on their performance characteristics in order to develop efficient systems. The present study conducts parametric analysis of a PTSC-driven trigeneration system with a novel energy distribution based on direct-fed ORC and bottom-cycled arrangement of double-effect absorption refrigeration cycle and Kalina cycle system. Three different ORC structures (simple, regenerative, and ORC integrated with intermediate heat exchanger - IHE) are proposed. Effect of key ORC parameters namely ORC evaporator pinch point temperature and pump inlet temperature is examined on the thermodynamic performance of systems. Decrease of pinch point temperature enhances overall efficiencies and heating power in all three configurations, and increases (decreases) the net electrical power for ORC and regenerative ORC (RORC) based systems. This also enhances the cooling power of the RORC based system, though it has no impact on the cooling power of the ORC and ORC-IHE based systems. Reduction of the ORC pump inlet temperature increases overall exergy efficiency in all hybrid systems and overall energy efficiency in the ORC and ORC-IHE based systems, whereas it slightly decreases for the RORC based system. Based on a comparative study, performance of the proposed systems is found to be higher than related solar-driven multi-generation systems in the literature. [ABSTRACT FROM AUTHOR]

Optimal thermo-economic integration of renewable energy sources with multi-generation energy systems is a prime research topic today. The present study proposes a multi-criteria evaluation method of such integration, based on combined heating and power (CHP), and combined cooling and power (CCP) scenarios, for three different solar intensities. Three novel solar-driven tri-generation systems are selected. They include different organic Rankine cycle (ORC) architectures and a Kalina cycle system (KCS) and a double-effect absorption refrigeration cycle as bottoming cycles. Evaluation of the tri-generation systems, both with and without the KCS system, indicates a performance improvement of up to 23% in various thermoeconomic characteristics when the KCS system is present. Selection of the suitable tri-generation system for each condition and optimization of the working fluid are carried out based on a multi-attribute decision-making method. P-xylene is found as the optimal organic working fluid for ORC and ORC (ORC integrated with internal heat exchanger) based systems, and benzene for the regenerative ORC-based system in both CHP and CCP scenarios. Multi-criteria analysis shows that ORC-based system outperforms other systems with net outranking flow of 0.44 (0.39) for CHP (CCP) application. The optimal configuration gives 95.6 M$ and 1.99 years for net present value and dynamic payback period, and 83.03% and 34.55% for energy and exergy efficiencies, respectively. [ABSTRACT FROM AUTHOR]

Although xylazine is widely used in domestic animals as a sedative, analgesic, and muscle relaxant, its side effects on the uterus prevent its utilization in pregnant animals or in embryo transfer. Although the effects of xylazine on increasing uterine contractions have been confirmed, no reliable report of fetal death due to xylazine administration has been published. Hyoscine is an anticholinergic medication that has antimuscarinic and antispasmodic effects in the uterine tissue of pregnant cattle during in vitro studies, therefore, we investigated if administration of xylazine in the last third of pregnancy could increase fetal death and if hyoscine could prevent its adverse effects. Twenty adult female rats, after mating with four adult male rats and confirming pregnancy, were randomly divided into two equal control and treatment groups. On the 18th day of pregnancy, the number of fetuses per rat was determined using ultrasonography. Rats in the treatment group received hyoscine (1 mg/kg, intraperitoneally) for 3 days. Subsequently, all rats were administered xylazine (10 mg/kg, intraperitoneally) for 3 days. On the 21st day of pregnancy, the number of living and dead fetuses was counted after laparotomy. Also, the weight and dimensions of the fetuses were measured. The results showed that although more fetuses lost their lives in the treatment group compared to the control group, the statistical difference in the percentage of fetal mortality in the two groups was not significant (p  0.05). In addition, the comparison of the mean weight, body length, and body width of living and dead fetuses in both groups showed that there was no statistically significant difference between these groups (p  0.05). It could be concluded that maternal xylazine intake in rats could cause about 18-25% of fetal mortality. However, the use of hyoscine to prevent fetal death induced by xylazine is not recommended. [ABSTRACT FROM AUTHOR]

Many cellular changes have been reported to play a role in the aging process of oocyte; however, few studies have been performed on the appropriate time and temperature for the storage. The main problem is the distance and time available for the transfer of oocytes to the laboratory, and protection of immature oocytes without reducing their ability to fertilize in vitro is very critical. The aim of this study was to compare the Embryo Holding (EH-Syngro) and HTCM-199 medium to store immature oocytes at room temperature without incubation. A total of 5268 oocytes were tested. The oocytes were stored at three temperature degrees including 4, 22 and 38 ° C for 6, 12, 18, and 24 hours. After spending the storage time, they were entered to the standard maturation environment and finally IVF was performed.There was no statistically significant difference between the experimental and control groups in terms of blastocyst production at storage of 6h. At 12 hours, oocyte maturation and blastocyst production in all groups were significantly lower than that of the standard group. EHT and HTCM-199 medium in our experiment showed that they can be useful for storing immature oocyte for up to 6 hours at room temperature and have no adverse effect on maturation of oocyte and blastocyst production, and most importantly do not need an incubator to transport the oocytes to the laboratory. [ABSTRACT FROM AUTHOR]

Introduction: In the last decades, magnetic nanoparticles have been considered and are being studied for employment in tumor therapy and imaging. Also, alongside their utilization in the role of MRI contrast factors, investigations of targeting tumor cells with biomolecules like anticancer drugs, antibodies, and siRNA, the utility of magnetic nanoparticles is evaluated. This preliminary work aimed to investigate the effects of iron oxide NPs on embryo growth and development with an emphasis on brain morphology and teratogenic effects. Methods: After recognizing the air sac with candling, one hundred sixty fertile eggs of the Ross 308 broiler strains were divided into 8 groups (n=20). Group 1 (control) received 0.3 mL serum normal. Groups 2, 3, and 4 received iron oxide nanoparticles as maghemite with doses of 100, 250, and 500 ppm, respectively. Groups 5, 6, 7, and 8 received iron oxide NPs as magnetite with doses of 100, 250, 500, and 2500 ppm, respectively. Twenty days after injections, death day, chicken, brain, liver, heart, bursa of Fabricius, and spleen weights and teratogenic samples were recorded, and brain tissues from all chickens were collected for histological evaluations. Results: The results demonstrated that iron oxide NPs had teratogenic effects such as the lack of formation of abdominal wall muscles and exposing the heart out of the thorax. Also, alterations were observed in the weight ratio of the liver, spleen, and bursa of Fabricius in experimental groups compared to the control group. In the microscopic assessment of the brain tissue, hyperemia, neuronophagia, edema around vessels, necrosis, and vacuolation of neurons were noticeable. Conclusion: It can be concluded that iron oxide NPs affect the growth and development of embryos and can cross the BBB and penetrate the brain tissue by affecting brain morphology. [ABSTRACT FROM AUTHOR]

In the present article, performance of a glazed photovoltaic thermal system integrated with phase change materials (GPVT/PCM) is numerically examined based on both energy and exergy viewpoints. The effect of PCM volumetric fraction and environmental temperature on thermal and electrical characteristics of the system is evaluated. A three-dimensional model of the system is simulated transiently in the ANSYS Fluent 18.2 using pressure-based finite volume method and SIMPLE algorithm selected for coupling pressure and velocity components. Validity of the numerical results is confirmed based on available data. The results indicate that PCM melting is more likely far from the riser tube and absorption of thermal energy be the PCM is mostly effective for filling the PCM container by around 2/3 of the volume. Increase of the PCM volumetric fraction reduces the module temperature and enhances the electrical performance of the system in terms of both energy and exergy efficiencies, while it decreases the thermal efficiency. An opposite trend is experienced by increase of the environmental temperature in which the thermal efficiency enhances and the electrical efficiency declines. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mastitis is an important disease that affects dairy herds worldwide. The Staphylococcus aureus (S. aureus) is the causative pathogen for mastitis. This pathogen has the tendency to biofilm forming, and may happen to antibiotic resistance. OBJECTIVES: The aim of this study was to characterize the biofilm formation of different genotypes and antibiotic resistance pattern of S. aureus isolated from the subclinical bovine mastitis in Tehran province. METHODS: The lactating dairy cows were screened for the subclinical mastitis. The isolates were identified by phenotypic method and the presence of the nuc gene. The biofilm forming and quantification was characterized using colorimetric assay. The S. aureus biofilm gene was evaluated using PCR assay. The antimicrobial susceptibility of the isolates was assessed using DAD method. The lowest antimicrobial concentration preventing the visible growth was construed by MIC50. The antibiotic susceptibility and MBECs for the bacteria embedded in the biofilms were determined by XTT method. RESULTS: The antimicrobials susceptibility test showed penicillin and ceftiofur to be less and more effective in vitro, respectively. The genotypic characterization showed that the highest and the lowest frequencies for icaD (75%) and fnbB (31.2%) genes, respectively. The biofilm formation was also characterized. The MBEC results for the bacterial biofilm showed resistance to ceftiofur in the biofilm state; however, these strains were susceptible to this agent in the planktonic state. CONCLUSIONS: The biofilm formation is a significant virulence factor that was detected at a high rate. It is antibiotic-resistant and responsible for the subclinical bovine mastitis that does not respond to the routine treatments. In order to control the infection achieve the effective treatment, and prevent the emergence of antibiotic-resistant bacteria, it is necessary to isolate the causative agent and determine the antimicrobial susceptibility. [ABSTRACT FROM AUTHOR]

Reconstruction of flow field from real sparse data by a physics-oriented approach is a current challenge for fluid scientists in the AI community. The problem includes feature recognition and implementation of AI algorithms that link data to a physical feature space in order to produce reconstructed data. The present article applies machine learning approach to study contribution of different flow-based features with practical fluid mechanics applications for reconstruction of the missing data of turbomachinery particle image velocimetry measurements. Support vector regression (SVR) and multi-layer perceptron (MLP) are selected as two robust regressors capable of modelling non-linear fluid flow phenomena. The proposed flow-based features are optimally scaled and filtered to extract the best configuration. In addition to conventional data-based validation of the regressors, a metric is proposed that reflects mass conservation law as an important requirement for a physical flow reproduction. For a velocity field including 25% of clustered missing data, the reconstruction accuracy achieved by SVR in terms of R 2-score is as high as 0.993 for the in-plane velocity vectors in comparison with that obtained by MLP which is up to 0.981. In terms of mass conservation metric, the SVR model by R 2-score up to 0.96 is considerably more accurate than the MLP estimator. For extremely sparse data with a gappiness of 75%, vector and contour plots from SVR and MLP were consistent with those of the original field. Comparison of the ML models outcome with the reconstruction made by six additional spatial interpolation methods indicates considerably higher performance of the SVR in terms of either the velocity-based or mass conservation based metrics. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to evaluate the effect of magnesium sulfate in the prevention of fetal growth restriction due to the impaired uterine blood supply in the rat model.Methods: A total number of 24 female rats were used in this study. They were mated overnight and randomly divided into control and treatment groups. After anesthesia and incising abdominal midline in day 17 of gestation, the uterine artery was occluded by an atraumatic clamp for 60 min. The rats of the control group received normal saline after surgery and the rats of treatment group received magnesium sulfate subcutaneously. The laparotomy was repeated on day 21 of gestation, and the number of alive and dead fetuses was counted in each horn. The viability of fetuses was evaluated. The weight of the placenta and fetuses and the distance between the head and tail as well as back to the abdomen of the fetuses were also measured. Samples of the amniotic fluid (AF) were collected during both surgeries for biochemical analyses of the glucose, urea, lactate, and pyruvate levels by an AutoAnalyzer.Results: Among the total fetuses in ischemic horn, only 50% survived in the control group. Dead fetuses had less body consistency and had a dark color. In contrary, only 7.6% of the fetuses in the treatment group were absorbed and 92.4% were completely healthy and developed. Parameters related to placenta weight, fetus weight, fetus length, and fetus width had significant differences and those of the treatment group were higher. Glucose and lactate levels of the AF in the treatment group were significantly lower and urea level was significantly higher than the control group in day 21 of gestation. The changes in pyruvate levels were not significant.Conclusion: In conclusion, magnesium sulfate may counteract with the effects of temporary uterine ischemia in pregnant rats and prevent intrauterine growth restriction. [ABSTRACT FROM AUTHOR]

BACKGROUND: Post-partum depression is has higher prevelance among other mental illness and herbal therapies are potential alternatives and adjuncts for its treatment. Hesperidin is the major flavonoid isolated from citrus fruits which has neuroprotective, antioxidant and antidepressant activity OBJECTIVES: We studied the effect of prepartum administration of Hesperidin on postpartum antidepressant- like effects in mice. METHODS: Twelve male and 40 female mice (28-30 gr) were randomly selected and after determination of the pregnancy using vaginal plaque, allocated into 4 experimental groups. Group 1 was kept as control and groups 2-4 were i.p. injected with hesperidne (0.1, 0.5 and 1 mg/kg) on days of 5, 8, 11, 14 and 17 of pregnancy. The control group received i.p. injection of the saline on the same days. Following postpartum, forced swimming test (FST), tail suspension test (TST) and open field tests were used to evaluate depressive-like antidepressant activity of hesperidin. Also, serum Malondialdehyde (MDA), glutathione peroxidase (GPx), superoxide dismutase (SOD) and total antioxidant capacity (TAC) were determined. RESULTS: Based on findings, administration of the different levels of the hesperidin (0.5 and 1 mg/kg) at GD 5, 8, 11, 14 and 17 significantly diminished immobility time (S) in TST and FST on postpartum mice in comparison to control group (P≤0.05). Pre-partum administration of hesperidin (0.1, 0.5 and 1 mg/kg) had no effect on OFT (P>0.05). Administration of the hesperidin (0.5 and 1 mg/kg) during the GD significantly diminished MDA levels on postpartum compared to control group (P≤0.05). Also, pre-partum administration of the hesperidin (0.1, 0.5 and 1 mg/kg) significantly increased SOD and GPx levels on postpartum mice in comparison to control group (P≤0.05). CONCLUSIONS: These results suggested pre-partum administration of hesperidin has antidepressant and antioxidant effect in postpartum mice. [ABSTRACT FROM AUTHOR]